UV Spectrometric Analyses Research Articles

Influence of age of fermented Terminalia chebula fruit extract in shell lime: An ancient lime putty production technique adopted in Indian heritage structures

The study examines the influence of fermentation age of 5% w/v extract (K5%) of Terminalia chebula fruit in shell lime, using a 0.75 K5%-to-binder ratio. The carbon dioxide evolution, UV-Spectrometric analysis of K5% followed by Gas chromatography and mass spectroscopy (GC-MS) of the slaked putty variants, identified the predominance of organic acids, fatty acids, and esters. The 90th day physical, mechanical, and durability testing confirmed the lowest water-accessible porosity at 31.07 ±0.11% v/v in K5%-4-90, with capillary porosity trending as K5%-4-90<K5%-7-90<K5%-14-90<R-90<K5%-1-90, affecting compressive strength. Mineralogical and morphological studies confirmed the formation of calcite (CaCO3) polymorphs and calcium oxalates via the oxalate-carbonate pathway. Further, thermogravimetric analysis (TGA) revealed the highest %CaCO3 in K5-4-90 and K5-7-90 samples, linked to carbonation extent. The study specifies that K5% at the 4th and 7th days of fermentation age significantly alters putty characteristics, supporting its widespread application and internal and external finishes in heritage structures.

L-proline Interaction with Methyl Linoleate Oxidation Products Formation in Dry System and at Temperatures: For Understanding in Low-Moisture Foods

Dry and low-moisture foods could experience a significant loss in nutritional value due to the process of methyl linoleate oxidation. L-proline could interact with lipid oxidation products, potentially modifying their formation and reaction path. However, there was a lack of research on the interaction between L-proline and methyl linoleate oxidation products in dry and low-moisture food matrices, which was a concern given the potential impact on food safety and nutrition. To address this knowledge gap, a study investigated the interaction between L-proline and the oxidation products of methyl linoleate in a dry system. The study examined the formation of methyl linoleate oxidation products such as conjugated dienes, hydroperoxide, and hexanal in the absence and presence of varying moles of L-proline at different temperatures. The formation of conjugated diene, hydroperoxide, and hexanal was analyzed using UV spectrometer analysis, xylenol orange, and DNPH derivatization HPLC-UV analysis. The results showed that adding proline to methyl linoleate samples stabilized conjugated diene and decreased hydroperoxide and hexanal levels as temperature increased, compared to the control sample. This suggests that L-proline effectively interacted with methyl linoleate oxidation products and altered their formation and oxidation path in the dry system. Overall, this study provided a basis for significantly enhancing understanding of the reactions between L-proline and methyl linoleate oxidation products in dry and low-moisture foods, offered practical implications for the food industry, and paved the way for future research.

Green synthesis of silver nanoparticles using Ocimum sanctum Linn. and its antibacterial activity against multidrug resistant Acinetobacter baumannii.

The biosynthesis of nanoparticles using the green route is an effective strategy in nanotechnology that provides a cost-effective and environmentally friendly alternative to physical and chemical methods. This study aims to prepare an aqueous extract of Ocimum sanctum (O. sanctum)-based silver nanoparticles (AgNPs) through the green route and test their antibacterial activity. The biosynthesized silver nanoparticles were characterised by colour change, UV spectrometric analysis, FTIR, and particle shape and size morphology by SEM and TEM images. The nanoparticles are almost spherical to oval or rod-shaped with smooth surfaces and have a mean particle size in the range of 55 nm with a zeta potential of -2.7 mV. The antibacterial activities of AgNPs evaluated against clinically isolated multidrug-resistant Acinetobacter baumannii (A. baumannii) showed that the AgNPs from O. sanctum are effective in inhibiting A. baumannii growth with a zone of inhibition of 15 mm in the agar well diffusion method and MIC and MBC of 32 µg/mL and 64 µg/mL, respectively. The SEM images of A. baumannii treated with AgNPs revealed damage and rupture in bacterial cells. The time-killing assay by spectrophotometry revealed the time- and dose-dependent killing action of AgNPs against A. baumannii, and the assay at various concentrations and time intervals indicated a statistically significant result in comparison with the positive control colistin at 2 µg/mL (P<0.05). The cytotoxicity test using the MTT assay protocol showed that prepared nanoparticles of O. sanctum are less toxic against human cell A549. This study opens up a ray of hope to explore the further research in this area and to improve the antimicrobial activities against multidrug resistant bacteria.

Pivotal Role of Microbes in Solid Waste Management

LLactic acid bacteria (LAB) are used widely in food microbiology as probiotics and biopreservatives to extend shelf life of food items. Lactic acid produced by LAB strains are precursor of polylactic acid(PLA) that has growing demand as bioplastics that are biodegradable in nature replacing traditional plastics. LAB have the potential to utilize polysaccharides from various sources and produce lactic acid. The aim of this study is to identify lactic acid producing strains of lactic acid bacteria(LAB) that have efficiency in utilizing biodegradable fragment of domestic solid waste collected from residential areas of Coimbatore municipality for three days. The main objective of this study is to convert the biodegradable solid waste into lactic acid, a precursor of Poly lactic acid- PLA used as bioplastic. Important chemical parameters of the solid waste like phosphate estimation, nitrate estimation, Total organic carbon estimation were done following Indian standard analytical methods. Glucose consumption efficiency of Lacto bacillus sp.in solid waste substrate was analyzed in UV spectrometer at620nm by Anthrone method. Estimation of lactic acid produced was done in UV spectrometric analysis at 390nm using iron lactate formation. In this study, lactic acid bacteria were isolated from samples of milk, curd, idli batter and screened for lactic acid production. Three isolates were chosen for the study each one from milk, curd, idli batter and from biochemical tests and morphology confirmed as Lacto bacillus sp. Solid waste collected was pretreated with dilute acid heating and hydrolysate obtained was used as substrate for lactic acid production under optimized parameters. Three different substrates were chosen for lactic acid production and the results were compared. The three isolates of Lacto bacillus sp.were good producers of lactic acid and utilized biodegradable solid waste in an effective manner. 3-5 gm/lit of lactic acid was produced by the three strains of Lacto bacillus sp .Segregation of domestic solid waste collected, comprised of 40% biodegradable fragment, 40% nondegradable plastic, 20%miscellaneous waste. Lactic acid production from biodegradable portion is a preliminary step experimented in this study progressing in polylactic acid PLA pathway indirectly reducing plastic pollution. In a similar manner, nonbiodegradable plastic waste can be minimized using Exopolysaccharide pathway by Xanthomonas sp.that is reviewed in this study. Disposal of solid waste in an economical and greener way is a smart method of saving environment. Bioconversion of plastic into pseudoplastic xanthan gum by Xanthomonas sp.(through exopolysaccharide pathway) are greener techniques to crush down the accumulated plastic mountains to ground level.

Separation and physico-chemical analysis of sericin protein from silk

Sericin protein was extracted from silk using a water-based method. The impact of sericin on the aquatic environment and its behavior under various temperature conditions were thoroughly investigated. To assess the total protein content in the solutions derived from silk at different temperatures, the Lowry method was employed. Subsequently, sericin protein was isolated in its pure form. In order to gain deeper insights into the characteristics of sericin, both IR-spectrometric and UV-spectrometric analyses were conducted. These analyses provided valuable information about the molecular structure and properties of the sericin protein. Additionally, the study focused on determining the composition of amino acids present in the sericin protein. For this purpose, high-performance liquid chromatography (HPLC) was employed, allowing for precise quantification and identification of individual amino acids within the protein. Through these comprehensive analytical techniques and experiments, researchers aimed to unravel the properties, behavior, and potential applications of sericin protein, contributing to a better understanding of its role and impact in various environmental and temperature conditions.

Optimizing harvest time of Cassia angustifolia Vahl Pennel. for maximum total sennoside content: A fast UV spectrometric analysis approach

Optimizing harvest time of Cassia angustifolia Vahl Pennel. for maximum total sennoside content: A fast UV spectrometric analysis approach

Comparative Study of High-Temperature Annealed and RTA Process β-Ga2O3 Thin Film by Sol–Gel Process

As a wide energy band gap semiconductor, a Ga2O3 thin film was prepared by the sol–gel process with different annealing processes. Since Ga2O3 is a type of metal oxide structure, an oxygen annealing process can be considered to remove oxygen defects. An effective oxygen annealing process can help form a β-Ga2O3 structure with reduced defects. In this study, different types of annealing effects for β-Ga2O3 were investigated and compared. An electric furnace process using thermal effect characteristics of and an Rapid Thermal Annealing (RTA) process applied with an infrared radiation light source were compared. Two and 4 h thermal annealing processes were conducted at 900 °C in the furnace. Meanwhile, to study the optical annealing effects, 2 h furnace at 900 °C + 15 min in rapid thermal annealing and only 15 min in rapid thermal annealing effects were compared, respectively. Through increasing the thermal annealing temperature and time, β-Ga2O3 can be formed even though a sol–gel process was employed in this experiment. An annealing temperature of at least 900 °C was required to form β-Ga2O3 thin film. Moreover, by introducing an RTA process just after the spinning process of thin film, a β-Ga2O3 thin film was formed on the sapphire substrates. Compared with the electric furnace process applied for 2 h, the RTA process performed in 15 min has a relatively short process time and results in similar structural and optical characteristics of a thin film. From the X-ray diffraction patterns and UV spectrometer analysis, optically annealed β-Ga2O3 thin films on the sapphire substrate showed a highly crystalized structure with a wide energy band gap of 4.8 eV.

Development and formulation of Aloe vera emulgel

Aloe vera is most popular in treatment of dermatological disorder in case of burn, tan and wound healing. The study was designed for crude Aloe vera extract, development of oil in water (o/w) emulsion, preparation of gel base using Aloe vera extract and formulation of the emulgel for topical application. The formulation was prepared by using carbomer 940 as polymer and isopropyl alcohol as penetration enhancer. The pH and viscosity of the Aloe vera emulgel were noticed to be 6.8 and 750 centipoise (cps) respectively. The interaction study between phytochemicals and the excipients was carried out using Fourier transform infrared (FTIR) spectroscopy. UV spectrometric analysis of plant extract was carried out. Dynamic light scattering (DLS) was performed to determine the particle size distribution of oil globules in emulsion. Mean particle size (oil globules) was observed to be 481 nm. Zeta potential and polydispersity index (PDI) was recorded to be -13.2 mV and 0.6 respectively.

Kinetic Rate Constants of Gold Nanoparticle Deposition on Silicon.

We fabricated gold nanoparticles on nanoporous silicon microparticles using electroless deposition in a hydrofluoric acid solution containing gold chloride. The reaction was followed by UV spectrometer analysis of the absorbance of the solution (proportional to the nanoparticle concentration) for two temperatures (20 and 50 °C). The results indicate that the process is autocatalytic, described by a pseudo-first-order reaction, the apparent rate constant kobs of which was determined by utilizing UV spectrometer data. We found that the reaction rate constant at 20 °C is 7 × 10-3 s-1 and that at 50 °C is 2.9 × 10-2 s-1. Scanning electron microscope (SEM) analysis of samples and diffusion-limited aggregation (DLA) simulations were used to validate the results. This study aims to resolve the kinetics of the electroless deposition of gold on silicon at the nanoscale, in the present state of art missing a quantitative characterization, for certain conditions of growth and given values of temperature and concentration of the reagents. Results may have applications to the synthesis of gold nanoparticles and their use as nanosensors, drug delivery systems, or metal nanometamaterials with advanced optical properties.

LED illumination-induced fading of traditional Korean pigments

Abstract Light is an important factor in the conservation of museum collections because of its strong electromagnetic characteristic that can degrade artifacts. To investigate the effects of illumination on paintings, particularly in museums equipped with popular light emitting diode (LED) lamp systems, we investigated the fading process of traditional Korean pigments. We used four illumination conditions: a combination of high and low color rendering index (CRI) at two light temperatures of Tcold = 5600 K and Twarm = 3200 K. Among all samples tested, realgar, also known as Wunghwang in Korea, showed the most marked change in color. UV spectrometric analyses after 100 h of exposure at 11 000 and at 5500 lux showed high color differences exceeding the color change threshold under all illumination conditions. When the illumination intensity was reduced to 300 lux, Tcold lamps showed a faster fading process than Twarm lamps did, suggesting that appropriate illuminating conditions can reduce the adverse effects of museum lighting systems. A further experiment using narrow-band, single-color, LED lamps showed how specific wavelength bands could influence the fading of artifacts In particular, we newly confirmed that discoloration of Wunghwang could be induced by the illumination of green light, in addition to blue light generally known to induce discoloration. These results demonstrate that the fading of a specific pigment of the artifacts in museum collections can be minimized by tuning the intensities of the wavelengths of light emitted by the museums’ lighting systems.

Evaluation of band gap energy and surface roughness for tin indium zinc oxide thin films by atomic force microscopy and electron spectroscopy

The SnInZnO thin film was prepared at room temperature by RF magnetron sputtering. The band gap of this film was investigated by REELS and UV-Spectrometer analysis. The surface morphology and the root mean square (RMS) roughness of SnInZnO thin films measured using atomic force microscopy (AFM). By using REELS with low energy (500 eV) and high energy (1500 eV) electron beams, the surface band gap as well as and the bulk energy band gap were measured. In addition, the surface roughness was evaluated by atomic force microscopy. The result shows that the band gaps are affected by the primary electron energies. The transmittance value of 80% in the visible light region has been achieved. The optical band gap was calculated by using Tauc’s relation from UV-Spectrometer analysis and compared to that of the band gap obtained by the REELS spectra.

Enzyme Inhibitory Radicinol Derivative from Endophytic fungus Bipolaris sorokiniana LK12, Associated with Rhazya stricta.

Endophytes, living inside plant tissues, play an essential role in plant growth and development, whilst producing unique bioactive secondary metabolites. In the current study, the endophytic fungus Bipolaris sorokiniana LK12 was isolated from the leaves of ethno-medicinal and alkaloidal rich Rhazya stricta. The bulk amount of ethyl acetate extract of fungus was subjected to advance column chromatographic techniques, which resulted in the isolation of a new radicinol derivative, bipolarisenol (1). It was found to be a derivative of radicinol. The structure elucidation was carried out by the combined use of 1D and 2D nuclear magnetic resonance, infrared spectroscopy, mass, and UV spectrometric analyses. The bipolarisenol was assessed for its potential role in enzyme inhibition of urease and acetyl cholinesterase (AChE). Results showed that bipolarisenol significantly inhibited the AChE activity with low IC50 (67.23 ± 5.12 µg·mL−1). Bipolarisenol inhibited urease in a dose-dependent manner with high IC50 (81.62 ± 4.61 µg·mL−1). The new compound also showed a moderate anti-lipid peroxidation potential (IC50 = 168.91 ± 4.23 µg·mL−1). In conclusion, endophytes isolated from medicinal plants possess a unique potential to be considered for future drug discovery.

Determination of the band gap energy for ternary material Sn-In-Zn-O thin films by electron spectroscopy and ultra-visible spectrometer

The SnInZnO thin film was prepared at room temperature by RF magnetron sputtering. The band gap of this film was investigated by REELS and UV-Spectrometer analysis. By using REELS with low energy (500 eV) and high energy (1500 eV) electron beams, the surface band gap as well as and the bulk energy band gap were measured. The result shows that the band gaps are affected by the primary electron energies. The transmittance value of 80% in the visible light region has been achieved. The optical band gap was calculated by using Tauc’s relation from UV-Spectrometer analysis and compared to that of the band gap obtained by the REELS spectra.

Cellular Recognition of Trimyristoylated Peptide or Enterobacterial Lipopolysaccharide via Both TLR2 and TLR4

Evidence for specific and direct bacterial product recognition through toll-like receptors (TLRs) has been emphasized recently. We analyzed lipopeptide analogues and enterobacterial lipopolysaccharide (eLPS) for their potential to activate cells through TLR2 and TLR4. Whereas bacterial protein palmitoylated at its N-terminal cysteine and N-terminal peptides derived thereof are known to induce TLR2-mediated cell activation, a synthetic acylhexapeptide mimicking a bacterial lipoprotein subpopulation for which N-terminal trimyristoylation is characteristic (Myr(3)CSK(4)) activated cells not only through TLR2 but also through TLR4. Conversely, highly purified eLPS triggered cell activation through overexpressed TLR2 in the absence of TLR4 expression if CD14 was coexpressed. Accordingly, TLR2(-/-) macrophages prepared upon gene targeting responded to Myr(3)CSK(4) challenge, whereas TLR2(-/-)/TLR4(d/d) cells were unresponsive. Through interferon-gamma (IFNgamma) priming, macrophages lacking expression of functional TLR4 and/or MD-2 acquired sensitivity to eLPS, whereas TLR2/TLR4 double deficient cells did not. Not only TLR2(-/-) mice but also TLR4(-/-) mice were resistant to Myr(3)CSK(4) challenge-induced fatal shock. d-Galactosamine-sensitized mice expressing defective TLR4 or lacking TLR4 expression acquired susceptibility to eLPS-driven toxemia upon IFNgamma priming, whereas double deficient mice did not. Immunization toward ovalbumin using Myr(3)CSK(4) as adjuvant was ineffective in TLR2(-/-)/TLR4(-/-) mice yet effective in wild-type, TLR2(-/-), or TLR4(-/-) mice as shown by analysis of ovalbumin-specific serum Ig concentration. A compound such as Myr(3)CSK(4) whose stimulatory activity is mediated by both TLR2 and TLR4 might constitute a preferable adjuvant. On the other hand, simultaneous blockage of both of the two TLRs might effectively inhibit infection-induced pathology.

Comparative mechanistic thermochemical decomposition analyses of liquid hexahydro-1,3,5-trinitro-13,5-triazine (RDX) using the kinetic deuterium isotope effect approach

The condensed phase kinetic deuterium isotope effect (KDIE) approach is applied to the thermochemical decomposition of liquid RDX and RDX- d 6 using two dissimilar thermal analysis techniques. Comparative KDIE results from isothermal differential scanning calorimetry (IDSC) and from direct RDX concentration depletion measurements by quenched UV spectrometric analysis confirm the proposed proportionality between IDSC heat evolution rates and the RDX concentration depletion rate. Additionally, these KDIE data verify the proposed rate-controlling mechanistic step previously reported from an isothermal thermogravimetric investigation of liquid RDX determined from weight loss rates. Observed mechanistic and kinetic differences between the cyclic six-membered RDX decomposition and its eight-membered HMX homologue are outlined.